CN115516601A

CN115516601A - Ion implantation device and robot arm

Info

Publication number: CN115516601A
Application number: CN202180018921.9A
Authority: CN
Inventors: 林群傑; 林伟政
Original assignee: Advanced Ion Beam Technology Inc
Current assignee: Advanced Ion Beam Technology Inc
Priority date: 2021-04-22
Filing date: 2021-04-22
Publication date: 2022-12-23
Also published as: WO2022222098A1

Abstract

The invention provides a mechanical arm and an ion implantation device. The long axis direction of the first arm, the second arm and the third arm is vertical to the Z axis direction. The front end of the second arm is pivoted to the rear end of the first arm. The front end of the third arm is pivoted to the rear end of the second arm. The lower end of the vertical arm is fixedly connected with the rear end of the third arm. The wafer holder is pivoted to the upper end of the vertical arm along a pivoting direction that is perpendicular to the long axis direction of the vertical arm and that is not parallel to the long axis direction of the third arm.

Description

Ion implantation device and robot arm

Technical Field

The invention relates to an ion implantation device and a mechanical arm for performing ion implantation.

Background

Conventional ion implantation processes typically use a scanning robot to perform wafer holding and implant angle adjustment. Unlike a transfer robot that transfers a wafer only in a horizontal plane, a scanning robot must allow the wafer to be switched between a horizontal plane and a vertical plane to receive the wafer provided by the transfer robot and then switch the wafer to a vertical plane to allow an ion beam to be directed from the side toward the wafer located in the vertical plane to perform ion implantation. In some processes, the scanning robot adjusts the plane of the wafer to form an angle with the incident direction of the ion beam, thereby allowing ion implantation to be performed at different incident angles.

The foregoing process suffers from several problems, first, the ion beam directed to the robot from the side or at an angle of incidence may cause mechanism aging that affects operation, increasing maintenance frequency.

Secondly, after the metal robot is bombarded by the ion beam, the metal particles are easy to separate from the surface of the robot, which results in the pollution in the vacuum chamber.

Finally, considering the size limitation of the vacuum chamber, it is necessary to consider that the arm operation should not occupy too much space and still complete the implantation process of the whole wafer. For example, in some ion implantation processes, a robot arm is rotated back and forth radially with respect to a pivot axis to perform one-dimensional arc scanning; if it is desired to perform an ion implantation process with two-dimensional scanning, the robot arm is driven by a drive motor located within the chamber to incrementally increase or decrease its height in the Z-axis direction in a two-dimensional zig-zag scan relative to the advancing ion beam to implant a uniform dose of ions in two dimensions into the workpiece.

However, although the above-mentioned scanning method can perform scanning along the Z-axis direction, the degree of freedom in the Z-axis direction is usually limited to 50mm to 140mm, and the diameter of a common wafer is usually 300mm, which obviously exceeds the scanning height range of the robot arm, so that it is difficult to perform large-area two-dimensional scanning using a common ion implantation apparatus, or to implement large-area two-dimensional scanning using a more complicated ion implantation apparatus, which increases the reaction chamber space and the equipment cost required by the ion implantation equipment.

DISCLOSURE OF THE INVENTION

In view of the above, an object of the present invention is to provide a robot arm. The robot is configured to move a workpiece along a scan axis to perform ion implantation of the workpiece, the scan axis being located on a horizontal plane (X-Y plane) and perpendicular to a Z-axis direction, the robot comprising: a first arm, including a front end and a rear end, wherein the long axis direction of the first arm is perpendicular to the Z axis direction; a second arm, including a front end and a rear end, wherein the long axis direction of the second arm is perpendicular to the Z axis direction and the front end of the second arm is pivoted to the rear end of the first arm; a third arm, including a front end and a rear end, wherein the long axis direction of the third arm is perpendicular to the Z axis direction, and the front end of the third arm is pivoted to the rear end of the second arm; a vertical arm, including an upper end and a lower end, the lower end of the vertical arm is fixedly connected with the rear end of the third arm; and a wafer holder having a holding face for holding the workpiece, the wafer holder being pivotally connected to the upper end of the vertical arm along a pivotal connection direction, the pivotal connection direction being perpendicular to the long axis direction of the vertical arm and the pivotal connection direction being non-parallel to the long axis direction of the third arm.

Applicants further propose an apparatus for ion implantation, comprising: a sliding seal assembly comprising: the fixing plate is connected with a cavity wall of a reaction chamber and is provided with a through hole extending along the Z-axis direction; a first sliding plate opposite to the reaction chamber and located on an outer surface of the fixing plate, the first sliding plate being slidable on the outer surface along the Z-axis direction, the first sliding plate having a first opening facing the through hole, and along the Z-axis direction, a diameter of the first opening being smaller than a diameter of the through hole; a second slide plate opposite to the reaction chamber and located on a first surface of the first slide plate, the second slide plate being slidable on the first surface, the second slide plate having a second opening facing the first opening, and along the Z-axis direction, the aperture of the second opening being smaller than the aperture of the first opening; the connecting rod is perpendicular to the Z-axis direction and is positioned in the second opening, and the connecting rod comprises a driving end, a rod body passing through the first opening and the through opening, and a connecting end positioned in the reaction chamber; the driving unit is connected to the driving end of the connecting rod and is positioned outside the reaction chamber, and the driving unit is used for driving the connecting rod to move along the Z-axis direction; and the aforementioned mechanical arm, wherein the length of the first arm is smaller than the length of the connecting rod, and the front end of the first arm is pivoted to the connecting end of the connecting rod.

The following detailed description of the embodiments of the invention, taken in conjunction with the accompanying drawings, will make it easier to understand the objects, technical contents, features and effects of the invention.

Brief description of the drawings

FIG. 1 is a schematic view of a robot in an initial state according to a first embodiment of the present invention;

FIG. 2 is a partial perspective view of a robot according to a first embodiment of the present invention;

FIG. 3 is a schematic view illustrating an operating state of a robot according to a first embodiment of the present invention;

FIG. 4 is a schematic view of a robot according to a second embodiment of the present invention;

FIG. 5 is a schematic view of a robot according to a third embodiment of the present invention;

FIG. 6 is an exploded view of the robot arm of the embodiment shown in FIG. 5;

fig. 7 is a schematic perspective view of an ion implantation apparatus according to a fourth embodiment of the present disclosure;

FIG. 8A is a schematic view of a first perspective of the sliding seal assembly of the embodiment of FIG. 7;

FIG. 8B is a schematic view of a second perspective of the sliding seal assembly of the embodiment of FIG. 7;

fig. 9 is a schematic diagram illustrating a usage state of the ion implantation apparatus of fig. 7 along a Z-axis direction according to an embodiment;

fig. 10 is a schematic diagram illustrating an ion implantation apparatus according to the embodiment of fig. 7 in use along an X-axis direction;

fig. 11 is a schematic perspective view illustrating an ion implantation apparatus according to a fifth embodiment of the present disclosure;

fig. 12 is a schematic diagram illustrating an operation state of the ion implantation apparatus of fig. 11 along an X-axis direction.

Wherein the reference numerals

N is a normal vector

R is ion beam

S1, S2 scanning axis

T1 through hole

T2 first opening

T3 second opening

W is width

X, Y, Z coordinate axes

Angle of inclination theta

D1 pivoting direction

D2 major axis direction of third arm

D3, D4 rotating shaft

D5 cutting line

1 sliding seal assembly

10 fixing plate

10a outer surface

12: first slide plate

12a first surface

14 second sliding plate

16: connecting rod

160 driving end

162 rod body

164 is a connecting end

18 drive unit

19 sliding rail unit

100 reaction chamber

102 chamber wall

2: mechanical arm

20 the first pivoting unit

21 first arm

210 front end

212 rear end of the cable

22 second pivot unit

23 second arm

230 front end

232 rear end

24: third pivoting unit

25 third arm

250 front end

252 back end

26 vertical arm

261 opening (C)

27 rotating mechanism

28: wafer holder

29 protective shell

Best mode for carrying out the invention

The following detailed description of the various embodiments of the invention, taken in conjunction with the accompanying drawings, is provided by way of illustration. In the description of the specification, numerous specific details are set forth in order to provide a more thorough understanding of the invention; however, the present invention may be practiced without some or all of these specific details. The same or similar elements in the drawings will be denoted by the same or similar symbols. It is specifically noted that the drawings are merely schematic and do not represent actual sizes or quantities of elements, and that some of the details may not be fully drawn for clarity of the drawings.

Fig. 1 is a schematic view of a robot arm in an initial state according to a first embodiment of the invention, please refer to fig. 1. According to some embodiments, the robot arm 2 comprises a first arm 21, a second arm 23, a third arm 25, a vertical arm 26 and a wafer holder 28. The long axis directions of the first arm 21, the second arm 23 and the third arm 25 are all perpendicular to the Z-axis direction and parallel to the horizontal plane (i.e., X-Y plane). The front end 230 of the second arm 23 is pivotally connected to the rear end 212 of the first arm 21, and the front end 250 of the third arm 25 is pivotally connected to the rear end 232 of the second arm 23. The lower end of the vertical arm 26 is secured to the rear end 252 of the third arm 25, and the upper end of the vertical arm 26 is coupled to the wafer holder 28. The wafer holder 28 has a holding face for carrying a workpiece such as a wafer. The wafer holder 28 may be an electrostatic chuck (chuck), but is not so limited. According to some embodiments, the upper end of the vertical arm 26 is provided with a rotation mechanism 27, the rotation mechanism 27 is connected to the wafer holder 28, and the rotation mechanism 27 can drive the wafer holder 28 to rotate with respect to the X-axis. For example, the rotation mechanism 27 drives the surface normal vector N of the wafer holder 28 to rotate to the direction perpendicular to the Z axis to face the ion beam R. The rotating mechanism 27 may be, but is not limited to, a motor, a gear set, a belt drive. For example, referring to fig. 2, a motor is disposed inside the vertical arm 26, and a rotating shaft of the motor is connected to a rear side of the wafer holder 28, so that an elevation angle (depression angle) of a holding surface of the wafer holder 28 can be adjusted, which may be one of methods of changing an incident angle of the ion beam, but the present invention is not limited thereto. In addition, referring to fig. 4 and 7, by changing the holding surface of the wafer holder 28, the wafer holder 28 can be switched between a wafer loading/unloading mode (wafer loading/unloading position) and an initial ion implantation mode (implantation position), wherein the wafer loading/unloading mode can be defined as the normal vector N of the holding surface of the wafer holder 28 is parallel to the coordinate axis Z; the initial ion implantation mode may be defined as the normal vector N of the holding surface being parallel to the coordinate axis Y, i.e., the direction in which the ion beam R travels.

According to some embodiments, the vertical arm 26 keeps the wafer holder 28 relatively away from the first, second and

third arms

21, 23, 25. In this way, the first arm 21, the second arm 23 and the third arm 25 are prevented from being irradiated by the ion beam, so that the mechanism is prevented from being aged, and the maintenance frequency is reduced. According to some embodiments, the rotating mechanism 27 includes a rotating shaft, a transmission element and a motor. The transmission element may be, but is not limited to, a belt, chain, link or gear set. For example, a rotating shaft is disposed at the upper end of the vertical arm 26, the rotating shaft is connected to the rear side of the wafer holder 28, a motor is disposed inside the hollow vertical arm 26, and the rotating shaft and the motor are connected by a belt to adjust the elevation angle (depression angle) of the holding surface of the wafer holder 28. In this way, the motor is disposed inside the vertical arm 26 or at the lower end of the vertical arm 26, thereby preventing the motor from being irradiated by the ion beam and increasing the service life of the motor with relatively high component cost. In addition, the wafer holder 28 is relatively far away from the first arm 21, the second arm 23 and the third arm 25, and when the surface materials of the first arm 21, the second arm 23 and the third arm 25 are made of metal, the ion beam does not irradiate the first arm 21, the second arm 23 and the third arm 25, so that the metal particle pollution in the vacuum chamber is not caused. Referring to fig. 2, according to some embodiments, the wafer holder 28 is disposed at the side of the vertical arm 26, and the third arm 25, the vertical arm 26 and the wafer holder 28, viewed from the ion beam incident direction, exhibit a structure of the type "12552525". In this way, neither the third arm 25 nor the vertical arm 26 is readily irradiated by the ion beam either in the forward direction or at an angle of incidence to the wafer holder 28, thereby avoiding the aforementioned problems of mechanism degradation or contamination. According to some embodiments, the wafer holder 28 is arranged on a rotating shaft and the length of the rotating shaft is long enough that the distance from the geometric center of the wafer holder 28 to the surface of the vertical arm 26 is greater than half the outer diameter of the holding surface. Therefore, the vertical arm 26 is not easily irradiated with the ion beam when the ion beam is directed toward the wafer holder 28. According to some embodiments, the surface of the vertical arm 26 facing the ion beam incident direction is a plane without curvature. Thus, even if the ion beam is directed toward the vertical arm 26, it will not cause the ion beam to reflect in multiple directions and affect the surrounding chamber. For example, referring to fig. 2, the main body of the vertical arm 26 may be a rectangular parallelepiped or a three-dimensional structure composed of a plurality of planes.

Referring to fig. 3, the first and

second arms

21 and 23 provide movement of the wafer holder 28 along the coordinate axis X during scanning according to some embodiments, in which the scanning axis S1 is parallel to the X-axis. The configuration of the third arm 25 allows the robot 2 to increase the freedom of movement of the wafer holder 28 along the plane defined by the coordinate axis Y and the coordinate axis Y, thereby allowing the angle of the wafer holder 28 with respect to the ion beam emission source to be adjusted to accommodate different process conditions. In addition, the length of the third arm 25 is sufficient to provide a relatively long transport distance, allowing the wafer holder 28 to be moved to a remote wafer exchange point to receive a wafer provided by the transport robot and then move it back into the spatial range in which ion implantation is to be performed. According to some embodiments, to provide stability during wafer loading or transfer, the vertical arm 26 is secured to the third arm 25 to ensure that the wafer orientation does not shift during transfer.

Referring to fig. 1, according to some embodiments, the wafer holder 28 is pivoted in a pivoting direction D1 of the vertical arm 26 perpendicular to the long axis direction of the vertical arm 26, and the pivoting direction D1 is not parallel to the long axis direction D2 of the third arm (presenting a skew line in space). According to some embodiments, an angle between the pivot direction D1 and the long axis direction D2 of the third arm is greater than 0 degree and less than or equal to 30 degrees. According to some embodiments, the length of the long axis of the third arm 25 is greater than the width W of the wafer holder 28 plus the vertical arm 26, and the angle between the pivot direction D1 and the long axis direction D2 of the third arm is consistent such that a tangent line of the holding surface of the wafer holder 28 passes through the third pivot unit 24. According to some embodiments, the third pivot unit 24 has a rotation axis D3, the first pivot unit 20 has a rotation axis D4, the holding surface of the wafer holder 28 has a tangent line D5 in the basic state of the robot 2 assembly, and the pivot direction D1 and the long axis direction D2 of the third arm have an angle such that the rotation axis D3, the rotation axis D4 and the tangent line D5 are coaxial. In this way, when the robot 2 is in the assembly ground state, the coaxial axis is aligned with the emission direction of the ion beam, thereby allowing the whole robot 2 to be calibrated. In addition, when the designer plans the moving path of the arm, the position of the wafer holder 28 in the X-Y plane can be ensured only by performing design adjustment with respect to the position of the third pivot unit 24 in the X-Y plane as a reference point. In addition, referring to fig. 1, with the above configuration, when the robot 2 is in the initial state, the occupied area (footprint) of the whole robot 2 is very small, which is beneficial for the space configuration of the foundry.

Fig. 4 is a schematic view of a robot according to a second embodiment of the invention, please refer to fig. 4. According to some embodiments, the vertical arm is configured with a cover (not shown) and an opening 261, the opening 261 is configured to correspond to the rotating mechanism 27 in the vertical arm 26, and the cover is detachably disposed on the opening. The detachable may refer to completely detaching the cover from the opening 261 or detaching the cover from the opening 261 with a hinge attached to the vertical arm 26. In this way, the rotating mechanism 27 can be replaced or repaired through the opening 261. According to some embodiments, the opening 261 and the cover are not oriented to the incident direction of the ion beam, so as to avoid the ion beam irradiation.

FIG. 5 is a diagram illustrating a robot according to a third embodiment of the present invention; fig. 6 is an exploded view of the robot arm shown in fig. 5 according to the embodiment, please refer to fig. 5 and fig. 6 together. According to some embodiments, the robot arm 2 includes a plurality of protective cases 29, the protective cases 29 being respectively disposed on the upper surface of the third arm 25, the side surface of the vertical arm 26, and the surface of the rear side of the wafer holder 28. According to some embodiments, to prevent the ion beam from directly striking the vertical arm 26 when the ion beam is directed toward the wafer holder 28, a protective shield 29 is provided at least on the surface of the vertical arm 26 facing the ion beam emission source. According to some embodiments, when the ion beam is directed at the wafer holder 28 at an inclination angle (for example, referring to fig. 11, ion implantation is performed with the scanning axis S2), in order to prevent the ion beam from directly irradiating the rear side of the wafer holder 28, a protective case 29 is provided at least on the surface of the rear side of the wafer holder 28. According to some embodiments, when the holding surface of the wafer holder 28 performs ion implantation at a depression angle, in order to prevent the ion beam reflected by the holding surface from directly irradiating the upper surface of the third arm 25, a protective cover 29 is provided at least on the upper surface of the third arm 25. According to some embodiments, when the holding surface of the wafer holder 28 performs ion implantation at a depression angle, in order to prevent the ion beam reflected by the holding surface from directly irradiating the lower surface of the chamber to cause contamination, the pivot direction D1 of the wafer holder 28 is not parallel to the long axis direction D2 of the third arm, and the wafer holder 28 is away from the emission source of the ion beam relative to the third pivot unit 24. In this way, during the ion implantation process, the protective shell 29 disposed on the upper surface of the third arm 25 can directly receive the ion beam reflected from the holding surface without irradiating the lower surface of the chamber, no matter where the third arm 25 is moved by the first arm 21 and the second arm 23. According to some embodiments, the surface of the protective shell 29 is made of graphite, silicon or silicide. The surface material may refer to a surface of a coating or a surface of a uniform material, such as a metal plate coated with silicide or a graphite plate.

Fig. 7 is a schematic perspective view of an ion implantation apparatus according to a fourth embodiment of the invention. Fig. 8A is a first perspective view of the sliding seal assembly of the embodiment of fig. 7. Fig. 8B is a second perspective view of the sliding seal assembly of the embodiment of fig. 7. Fig. 9 is a schematic diagram illustrating a usage state of the ion implantation apparatus of fig. 7 along a Z-axis direction. Fig. 10 is a schematic diagram illustrating a usage state of the ion implantation apparatus of fig. 7 along an X-axis direction.

Referring to fig. 7 to 10 together, an ion implantation apparatus according to an embodiment of the present disclosure includes a sliding seal assembly 1 and a robot 2. The ion implantation device is located in a reaction chamber 100 of the ion implantation apparatus. Herein, the reaction chamber 100 is spatially defined by an X-axis direction, a Y-axis direction, and a Z-axis direction, and the three axes are perpendicular to each other, and in the present embodiment, the ion beam R travels in parallel to the Y-axis direction and is injected into the reaction chamber 100, but the invention is not limited thereto.

The sliding seal assembly 1 includes a stationary plate 10, a first slide plate 12, a second slide plate 14, connecting rods 16, and a drive unit 18. The sliding seal assembly 1 is located at the side of the reaction chamber 100, and the sliding seal assembly 1 is connected to the chamber wall 102 through the fixing plate 10. For example, the fixing plate 10 is connected to the chamber wall 102 of the reaction chamber 100, such as: the fixing plates 10 are adjacent to the cavity wall 102 and connected to each other, or the fixing plates 10 are integrated with the cavity wall 102 to form a whole. The fixing plate 10 has a through hole T1. The through-hole T1 penetrates from the outer surface 10a to the inside in the Y-axis direction, the through-hole T1 communicates with the reaction chamber 100, and the cross section of the through-hole T1 is elongated, for example, the through-hole T1 is an elliptical opening whose major axis direction extends in the Z-axis direction and whose minor axis direction extends in the X-axis direction. The through hole T1 has a moving space extending in the Z-axis direction, and the connecting rod 16 can pass through the through hole T1 and move in the Z-axis direction.

The first slide plate 12 is located at an outer surface 10a of the fixed plate 10 and is located at opposite sides of the fixed plate 10 from the reaction chamber 100, respectively. The first sliding plate 12 has a first opening T2, and the first opening T2 faces the through opening T1 and communicates with each other, wherein, viewed along the Z-axis direction, the aperture of the first opening T2 is smaller than the aperture of the through opening T1, and herein, the first sliding plate 12 is located on the outer surface 10a and covers at least a part of the through opening T1. The first opening T2 penetrates from the first surface 12a of the first slide plate 12 to the inside in the Y-axis direction, and the first opening T2 communicates with the through hole T1. In addition, the cross section of the first opening T2 is elongated, for example, the first opening T2 is an elliptical opening, the major axis direction of which extends along the Z-axis direction, and the minor axis direction of which extends along the X-axis direction. The first opening T2 has a moving space extending along the Z-axis direction, and the connecting rod 16 can pass through the first opening T2 and move along the Z-axis direction.

The second sliding plate 14 is located on the first surface 12a of the first sliding plate 12, and is located on the opposite side of the first sliding plate 12 from the fixed plate 10. The second sliding plate 14 has a second opening T3, and the second opening T3 faces the first opening T2 and is communicated with each other, wherein, viewed along the Z-axis direction, the aperture of the second opening T3 is smaller than the aperture of the first opening T2, and herein, the second sliding plate 14 is located on the first surface 12a and covers at least a part of the first opening T2. The second opening T3 penetrates inward from the outer surface of the second slider 14 in the Y-axis direction, and the second opening T3 communicates with the first opening T2. In addition, the second opening T3 has a through hole space for the connection rod 16 to pass through, for example, the cross-sectional shape of the second opening T3 corresponds to the cross-sectional shape of the connection rod 16, and the connection rod 16 penetrates through the second opening T3 and is firmly connected to each other, but not limited thereto. Therefore, the second sliding plate 14 uses the second opening T3 to accommodate the connecting rod 16, so that the connecting rod 16 can pass through the second opening T3 and move along the Z-axis direction.

The connecting rod 16 is located at the second opening T3 of the second slide plate 14, and the connecting rod 16 extends in the Y-axis direction, perpendicular to the Z-axis direction. The connecting rod 16 includes a driving end 160, a rod 162 and a connecting end 164 connected to each other. The driving end 160 is located outside the reaction chamber 100, the rod 162 extends toward the reaction chamber 100 through the second opening T3, the first opening T2 and the through opening T1 along the Y-axis direction, and the connecting end 164 is located inside the reaction chamber 100. The driving unit 18 is located outside the reaction chamber 100, and the driving unit 18 is connected to the driving end 160 of the connecting rod 16. The drive unit 18 may be, but is not limited to, a stepper motor or a jack to raise or lower the drive end 160. According to some embodiments, the driving unit 18 is disposed outside the reaction chamber 100 and detachably connected to the driving end 160, so as to facilitate maintenance of the driving unit 18 and equipment maintenance without interfering with the vacuum state of the reaction chamber 100. In this manner, when the driving unit 18 fails, the driving unit 18 is quickly replaced to continue the process without breaking the vacuum in the reaction chamber 100. According to some embodiments, the driving unit 18 is directly connected to the driving end 160. In one embodiment, the connecting rod 16 may be a feed-through tube having a pipe therein for disposing electronic components, such as but not limited to conductive circuits and sensing elements, through the cavity wall 102 to enter the reaction chamber 100, for example, the robot 2 in the reaction chamber 100 may be connected to an external control circuit and/or power supply through the connecting rod 16, but not limited thereto.

According to some embodiments, the robot 2 is located in the chamber 100 and is disposed on the connecting rod 16. According to some embodiments, the robot 2 includes a first pivot unit 20, a second pivot unit 22 and a third pivot unit 24, the front end 210 of the first arm 21 of the robot 2 is pivoted to the connecting end 164 of the connecting rod 16 through the first pivot unit 20, and the length of the first arm 21 is smaller than the length of the connecting rod 16, so as to avoid the interference between the robot 2 and the cavity wall 102 mechanism. The front end 210 of the first arm 21 is connected to the first pivot unit 20. The front end 230 of the second arm 23 is connected to the second pivot unit 22, the front end 230 of the second arm 23 is pivoted to the rear end 212 of the first arm 21, the front end 250 of the third arm 25 is connected to the third pivot unit 24, and the front end 250 of the third arm 25 is pivoted to the rear end 232 of the second arm 23. The first pivot unit 20 allows the first arm 21 to rotate relative to the Z-axis direction, the second pivot unit 22 allows the second arm 23 to rotate relative to the Z-axis direction, and the third pivot unit 24 allows the third arm 25 to rotate relative to the Z-axis direction. In brief, the robot 2 uses a plurality of robot arms to connect and pivot with each other via a plurality of pivot units to control the scanning orientation, angle and motion path of the wafer holder 28. Here, the robot arm 2 drives the wafer holder 28 to move along a scanning axis S1, wherein the scanning axis S1 is parallel to the horizontal plane and perpendicular to the Z-axis direction.

Referring to fig. 7 and 10 together, in one embodiment, the reaction chamber 100 has a Spot beam (Spot beam) implanted along the Y-axis direction for scanning the wafer point by point. In one embodiment, the ion beam R may also be a Ribbon beam (Ribbon beam), the scanning axis S1 of the wafer holder 28 is parallel to the X-axis direction, and the scanning axis S1 is perpendicular to the traveling direction of the ion beam R. In other words, the movement trajectory of the wafer holder 28 along the scanning axis S1 is constantly maintained at a perpendicular angle with respect to the traveling direction of the ion beam R during the ion implantation scanning, which is defined as Linear scan (Linear scan). Specifically, the robot arm 2 drives the wafer holder 28 to move in the X-axis direction along the scanning axis S1, and the wafer holder 28 is driven to move in the Z-axis direction by the connecting rod 16 of the sliding seal assembly 1, so that the ion implantation apparatus receives the ion beam R to implant a workpiece (not shown), such as a wafer, on the wafer holder 28 at a vertical angle, thereby implementing a two-dimensional (the plane of the coordinate axis X-the coordinate axis Z) linear scanning (2D linear scan) ion implantation process. In accordance with some embodiments, when using a spot beam (spot beam) for ion profiling, a two-dimensional linear scan may completely scan the spot beam across the entire surface of the wafer in a quasi-continuous zig-zag path (zig-zag); when a ribbon ion beam (ribbon beam) is used for ion implantation, linear scanning is usually sufficient because the height of the ribbon ion beam is usually larger than the diameter of the wafer.

The inventor has recognized that, in addition to the difficulty of implementing two-dimensional linear scanning, the conventional slide sealing mechanism of the conventional ion implantation apparatus only uses a single slide plate to cover the slit on the chamber wall 102, wherein the single slide plate slides up and down while still air-tightly covering the slit, so that the plate height along the Z-axis direction needs to be twice as large as the diameter of the slit, resulting in a large layout space for the single slide plate on the chamber wall 102, and increasing the space of the reaction chamber 100 required by the ion implantation apparatus and the apparatus cost.

With the above-described ion implantation apparatus structure, the sliding seal assembly 1 slides relative to the fixed plate 10 through a multi-piece continuous sliding assembly such as the first sliding plate 12 and the second sliding plate 14, and hermetically covers the through hole T1 of the fixed plate 10, instead of using a single sliding plate disposed on the fixed plate 10. Referring to fig. 7 and 9, when the connecting rod 16 of the sliding seal assembly 1 moves upward in the Z-axis direction in the reaction chamber 100, the first sliding plate 12, the second sliding plate 14 and so on cover a portion of the through hole T1 along the Z-axis direction, specifically, the first sliding plate 12 body slides upward for a certain distance and covers a portion of the opening of the through hole T1, and then the second sliding plate 14 body moves upward for a certain distance and covers the remaining portion of the opening of the through hole T1, and at the same time, the connecting rod 16 is allowed to pass through the chamber wall 102 of the reaction chamber 100, and the driving unit 18 drives the connecting rod 16 to move in the reaction chamber 100 along the Z-axis direction. In other words, the first sliding plate 12 and the second sliding plate 14 cooperate to perform the sliding sealing operation, and the occupied space can be reduced. At this point, the first sliding plate 12 and the second sliding plate 14 are still located substantially around the sliding seal assembly 1 and do not protrude significantly upward, which greatly reduces the required layout space of the chamber wall 102 along the Z-axis direction, further saving the volume of the reaction chamber 100 and the equipment cost.

In at least one embodiment, at least one of the first pivot unit 20, the second pivot unit 22 and the third pivot unit 24 may be a stepping motor, so as to accurately control the following components: the movement of the robot arms, such as the first arm 21, the second arm 23, and the third arm 25, improves the precision of the ion implantation process.

In at least one embodiment, the through hole T1 of the sliding seal assembly 1 is a long and narrow opening, and the aperture of the through hole T1 is greater than or equal to a wafer diameter, for example, the aperture of the through hole T1 along the Z-axis direction is 450mm, which can implement a two-dimensional scanning (2D scan) ion implantation process.

With reference to fig. 8A and 8B, in at least one embodiment, the sliding seal assembly 1 further includes a sliding rail unit 19. The slide rail unit 19 is disposed on the outer surface 10a of the fixing plate 10, and the slide rail unit 19 may be a linear groove or a flange, etc. for moving the first sliding plate 12 and the second sliding plate 14 relative to the fixing plate 10. According to some embodiments, the upper edge of the slide rail unit 19 is higher than the upper edge of the fixing plate 10, so as to provide stability to the first sliding plate 12 and the second sliding plate 14 over the entire moving path. In another embodiment, the sliding seal assembly 1 further includes a first sealing element and a second sealing element. For example, the first sealing element and/or the second sealing element may be an annular gasket (O-ring). The first sealing element is sandwiched between the fixed plate 10 and the first sliding plate 12. The first sealing element is located on the first sliding plate 12 and surrounds the periphery of the first opening T2, increasing the air tightness of the sliding seal assembly 1. The second sealing element is sandwiched between the first slide plate 12 and the second slide plate 14. The second sealing element is located on the second sliding plate 14 and surrounds the periphery of the second opening T3, increasing the air tightness of the sliding seal assembly 1.

Fig. 11 is a schematic perspective view of an ion implantation apparatus according to a fifth embodiment of the present disclosure. Fig. 12 is a schematic diagram illustrating an operation state of the ion implantation apparatus of fig. 11 along an X-axis direction. Referring to fig. 11 and 12 together, in one embodiment, the reaction chamber 100 has an ion beam R implanted along the Y-axis direction, wherein the scanning axis S2 of the wafer holder 28 is inclined at an angle θ with respect to the X-axis direction, i.e., the movement track of the wafer holder 28 along the scanning axis S2 is constantly maintained at a diagonal angle (not 90 degrees) with respect to the traveling direction of the ion beam R during the ion implantation scanning process, and the ion implantation performed under the diagonal angle is performed ideally at the same distance from the ion beam to the wafer surface, which is defined as concentric scanning (Isocentric scan). Specifically, the robot arm 2 drives the wafer holder 28 to move along the scanning axis S2 in a horizontal plane with the X-Y axis, and under the inclined path, the angle of the ion beam R injected into the wafer surface is fixed, and the distance of the ion beam R reaching the wafer surface during ion implantation is equal. In addition, in one implementation, if the wafer holder 28 is moved in the Z-axis direction by the driving action of the connecting rod 16 of the sliding seal assembly 1 under the condition that the spot-shaped ion beam is used, the ion implantation apparatus receives the ion beam R to obliquely implant a workpiece (not shown) such as a wafer on the wafer holder 28, and a two-dimensional iso-center scanning (2D iso-center scan) ion implantation process can be realized.

In summary, some embodiments of the present invention provide a robot 2, wherein the robot 2 adjusts the incident angle of the ion beam R to the wafer by the third arm 25, and the wafer holder 28 is away from the first arm 21, the second arm 23, and the third arm 25 by the vertical arm 26, so as to reduce the probability of the ion beam R irradiating most of the body of the robot 2, prolong the service life, and avoid particle contamination. Some embodiments of the present invention provide a robot arm 2, wherein the robot arm 2 allows a tangent line D5 of the wafer holder 28, a rotation axis D3 of the third pivot unit 24, and a rotation axis D4 of the first pivot unit 20 to be coaxial when in a ground state, so that the coaxial axes are aligned with an incident direction of the ion beam R only to complete the calibration. In some embodiments, the present invention provides an ion implantation apparatus, which mainly utilizes a multi-piece continuous sliding assembly, such as the first sliding plate 12 and the second sliding plate 14, to respectively slide along the Z-axis direction relative to the fixing plate 10/chamber wall 102 and hermetically cover a partial region of the through-hole T1, thereby greatly reducing the required layout space of the sliding sealing assembly 1 and the chamber wall 102 along the Z-axis direction, and further saving the volume of the reaction chamber 100 and the equipment cost. At the same time, the connecting rod 16 is allowed to pass through the chamber wall 102 of the reaction chamber 100 and drives the robot 2 in the reaction chamber 100 to move in the Z-axis direction to implement a two-dimensional linear/concentric scan (2D linear/iso-centric scan), thereby implanting the ion beam R with a uniform dose into the workpiece at a vertical or oblique angle in two dimensions.

The present invention is capable of other embodiments, and various changes and modifications can be made by one skilled in the art without departing from the spirit and scope of the invention.

Claims

A robot configured to move a workpiece along a scan axis for performing ion implantation of the workpiece, the robot comprising:

a first arm, including a front end and a rear end, wherein the long axis direction of the first arm is perpendicular to a Z-axis direction;

a second arm, including a front end and a rear end, wherein the long axis direction of the second arm is perpendicular to the Z axis direction and the front end of the second arm is pivoted to the rear end of the first arm;

a third arm, including a front end and a rear end, wherein the long axis direction of the third arm is perpendicular to the Z axis direction, and the front end of the third arm is pivoted to the rear end of the second arm;

a vertical arm, including an upper end and a lower end, the lower end of the vertical arm is fixedly connected with the rear end of the third arm;

a wafer holder having a holding face for holding the workpiece, the wafer holder being pivoted to the upper end of the vertical arm in a pivot direction; and

a rotation mechanism pivotally connecting the wafer holder to the vertical arm.
The robot of claim 1, wherein the pivoting direction is perpendicular to the long axis of the vertical arm and the pivoting direction is not parallel to the long axis of the third arm.
The robot arm as claimed in claim 2, wherein an angle between the pivot direction and a long axis direction of the third arm is greater than 0 degree and less than or equal to 30 degrees.
The robot of claim 1, wherein the third arm, the vertical arm, and the wafer holder collectively form a 12552letter shape.
The robot of claim 1, wherein the distance from the geometric center of the wafer holder to the surface of the vertical arm is greater than half the outer diameter of the holding surface.
The robot of claim 1, wherein the vertical arm has a non-curved surface on its side surface facing the ion beam incident direction.
The robot of claim 1, wherein the wafer holder has a tangential surface, the first arm has a pivot unit at a front end thereof, the pivot unit of the first arm has a first rotation axis, the third arm has a pivot unit at a front end thereof, the pivot unit of the third arm has a second rotation axis, and when the robot is in an assembled state, an angle between the pivot direction and a long axis direction of the third arm is such that the tangential surface, the first rotation axis and the second rotation axis are coaxial.
The robot of claim 1, wherein the vertical arm further comprises a cover and an opening, the opening is disposed at a position corresponding to the rotation mechanism, and the cover is detachably disposed on the opening.
The robot of claim 1, wherein the rotation mechanism comprises a shaft disposed at an upper end of the vertical arm and adapted to pivotally connect the wafer holder to the vertical arm, a transmission element disposed at a lower end of the vertical arm, and a motor adapted to transmit power from the motor to the shaft.
The robot of claim 1, further comprising at least one protective shell disposed on one or more of the following surfaces: an upper surface of the third arm, a side surface of the vertical arm, and a surface of a backside of the wafer holder.
The robot arm as recited in claim 10, wherein the protective shell comprises graphite, silicon or silicide.
The robot of claim 1, wherein the wafer holder is configured to hold the workpiece to subject the workpiece to ion implantation by a ribbon beam having a long side and a short side and the length of the long side is greater than the diameter of the workpiece.
A robot as claimed in claim 12, wherein the ribbon ion beam is transported parallel to a Y-axis direction and the long side of the ribbon ion beam is perpendicular to an XY-plane, the robot being configured to adjust the holding surface of the wafer holder perpendicular to the XY-plane and to adjust the scan axis parallel to an X-axis direction.
A robot as claimed in claim 12, wherein the ribbon beam is transported in a direction parallel to a Y-axis direction with the long dimension of the ribbon beam perpendicular to an XY-plane, the robot being configured to adjust the holding surface of the wafer holder perpendicular to the XY-plane and to adjust the scan axis to be at an angle to an X-axis direction.
The robot of claim 13 or 14, wherein the ribbon beam is equidistant from any point on the surface of the workpiece during ion implantation of the workpiece along the scan axis.
An apparatus for ion implantation, comprising:

a sliding seal assembly comprising:

the fixing plate is connected with a cavity wall of a reaction chamber and is provided with a through hole extending along the Z-axis direction;

a first sliding plate opposite to the reaction chamber and located on an outer surface of the fixing plate, the first sliding plate being slidable on the outer surface along the Z-axis direction, the first sliding plate having a first opening facing the through hole, and along the Z-axis direction, a diameter of the first opening being smaller than a diameter of the through hole;

a second slide plate opposite to the reaction chamber and located on a first surface of the first slide plate, the second slide plate being slidable on the first surface, the second slide plate having a second opening facing the first opening, and along the Z-axis direction, the aperture of the second opening being smaller than the aperture of the first opening;

the connecting rod is perpendicular to the Z-axis direction and is positioned in the second opening, and comprises a driving end, a rod body passing through the first opening and the through opening, and a connecting end positioned in the reaction chamber; and

the driving unit is connected to the driving end of the connecting rod and is positioned outside the reaction chamber, wherein the driving unit is used for driving the connecting rod to move along the Z-axis direction; and

a robot as claimed in any of claims 1 to 5, wherein the length of the first arm is less than the length of the connecting rod, the front end of the first arm being pivotally connected to the connecting end of the connecting rod.
The apparatus according to claim 16, wherein the through opening is an elongated opening.
The apparatus according to claim 17, wherein the aperture of the through-hole is greater than or equal to a wafer diameter.
The apparatus according to claim 16, wherein the sliding seal assembly further comprises:

a first sealing element located between the fixed plate and the first sliding plate, the first sealing element surrounding and located at the periphery of the first opening of the first sliding plate; and

a second sealing element positioned between the first slide plate and the second slide plate, the second sealing element surrounding and positioned at a periphery of the second opening of the second slide plate.
The apparatus according to claim 19, wherein at least one of the first sealing member and the second sealing member comprises a ring-type gasket.